If the radius of a circle is 4, what is the area expressed in terms of π?

If the radius of a circle is 4, what is the area expressed in terms of π?

• A. 8π
• B. 16π
• C. 12π
• D. 20π

Answer: (B)

To find the area of a circle, you use the formula: \[ A = πr^2 \] where \( A \) is the area, \( π \) is a mathematical constant approximately equal to 3.14, and \( r \) is the radius of the circle. In this case, the radius is given as 4. Thus, you would substitute 4 into the formula: \[ A = π(4^2) \] Calculating \( 4^2 \) gives you 16. Therefore, the area would be: \[ A = π(16) \] This simplifies to: \[ A = 16π \] So, the area of the circle expressed in terms of \( π \) is \( 16π \). This is why the answer is correctly identified as the one that states 16π.

To find the area of a circle, you use the formula:

[ A = πr^2 ]

where ( A ) is the area, ( π ) is a mathematical constant approximately equal to 3.14, and ( r ) is the radius of the circle.

In this case, the radius is given as 4. Thus, you would substitute 4 into the formula:

[ A = π(4^2) ]

Calculating ( 4^2 ) gives you 16. Therefore, the area would be:

[ A = π(16) ]

This simplifies to:

[ A = 16π ]

So, the area of the circle expressed in terms of ( π ) is ( 16π ). This is why the answer is correctly identified as the one that states 16π.